Adhesion tester

Abstract

An adhesion tester includes a dolly to be adhered to a coating to be tested; the dolly including at least a portion of a spherical surface; a frame having a hollow portion in a region thereof, in which region the dolly fits; a hydraulic piston within the frame; and a quick connect coupler for connecting the hydraulic piston to the dolly; the coupler including a plurality of ball bearings aligned so as to engage with a lower half of the spherical surface of the dolly so as to connect the dolly with the coupler.

What is claimed is: 
     
       1. An adhesion tester, comprising: a dolly to be adhered to a coating to be tested;   the dolly including an inclined peripheric surface extending circumferentially around an outside edge of the dolly;   a frame having a portion for receiving the dolly;   means for applying a retractive force between the frame and the dolly; and   a coupler for connecting the applying means to the dolly;   the coupler including a plurality of low friction contact points for engaging with the inclined peripheric surface of the dolly while enabling relative pivoting of the coupler with respect to an axial direction of the dolly.   
     
     
       2. The adhesion tester of claim 1, wherein the contact points are spherical ball bearings and the inclined surface has a radius that is greater than a radius of the ball bearings. 
     
     
       3. The adhesion tester of claim 1, wherein the inclined surface constitutes a truncated sphere. 
     
     
       4. The adhesion tester of claim 3, wherein the contact points are spherical ball bearings. 
     
     
       5. The adhesion tester of claim 3, wherein the coupler is a quick release coupler. 
     
     
       6. The adhesion tester of claim 1, wherein the applying means includes a hydraulic piston. 
     
     
       7. The adhesion tester of claim 1, wherein the applying means includes a pneumatic piston. 
     
     
       8. An adhesion tester, comprising: a dolly to be adhered to a coating to be tested;   the dolly including an inclined annular surface extending circumferentially around an outside edge of the dolly, said surface having a predetermined height with respect to an axis of the dolly;   a frame having a portion for receiving the dolly;   means for applying a retractive force between the frame and the dolly; and   a coupler for connecting the applying means to the dolly;   the coupler including a plurality of low friction contact points for engaging with the inclined annular surface of the dolly so as to connect the dolly with the coupler, the contact points having a dimension that is less than the predetermined height so as to enable relative pivoting of the coupler with respect to an axial direction of the dolly by moving the contact points along the annular surface.   
     
     
       9. The adhesion tester of claim 8, wherein the contact points are spherical ball bearings and the inclined surface has a radius that is greater than a radius of the ball bearings. 
     
     
       10. The adhesion tester of claim 8, wherein the inclined surface constitutes a truncated sphere. 
     
     
       11. The adhesion tester of claim 10, wherein the contact points are spherical ball bearings. 
     
     
       12. The adhesion tester of claim 8, wherein the coupler is a quick release coupler. 
     
     
       13. The adhesion tester of claim 8, wherein the applying means includes a hydraulic piston. 
     
     
       14. The adhesion tester of claim 8, wherein the applying means includes a pneumatic piston. 
     
     
       15. An adhesion tester, comprising: a dolly to be adhered to a coating to be tested;   a frame having a portion for receiving the dolly;   means for applying a retractive force between the frame and the dolly; and   a coupler for connecting the applying means to the dolly; and   means for enabling the coupler to engage the dolly in a self-centering manner by enabling relative pivoting of the coupler with respect to an axial direction of the dolly, said means including an inclined peripheric surface on the dolly and low friction contact points on the coupler.   
     
     
       16. The adhesion tester of claim 15, wherein the contact points are spherical ball bearings and the inclined surface has a radius that is greater than a radius of the ball bearings. 
     
     
       17. The adhesion tester of claim 15, wherein the inclined surface constitutes a truncated sphere. 
     
     
       18. The adhesion tester of claim 17, wherein the contact points are spherical ball bearings. 
     
     
       19. The adhesion tester of claim 15, wherein the coupler is a quick release coupler. 
     
     
       20. The adhesion tester of claim 15, wherein the applying means includes a hydraulic piston. 
     
     
       21. The adhesion tester of claim 15, wherein the applying means includes a pneumatic piston. 
     
     
       22. An adhesion tester, comprising: a dolly to be adhered to a coating to be tested;   the dolly including at least a portion of a spherical surface;   a frame having a hollow portion in a region thereof in which region the dolly fits;   a hydraulic piston within the frame; and   a quick connect coupler for connecting the hydraulic piston to the dolly;   a coupler for connecting the applying means to the dolly; and   the coupler including a plurality of ball bearings aligned so as to engage with a lower half of the spherical surface of the dolly so as to connect the dolly with the coupler.   
     
     
       23. The adhesion tester of claim 22, wherein the spherical surface has a radius that is greater than a radius of the ball bearings. 
     
     
       24. An adhesion tester according to claim 1, wherein: the dolly includes a body portion extending along a longitudinal axis and the low friction contact points engage the inclined peripheric surface of the dolly to allow a limited range of relative motion between the contact points and the inclined peripheric surface in an axial direction.   
     
     
       25. An adhesion tester according to claim 8, wherein: the dolly includes a body portion extending along a longitudinal axis and the low friction contact points have a dimension along the longitudinal axis that is less than the predetermined height of the inclined annular surface of the dolly, thereby allowing a limited range of relative motion between the contact points and the inclined peripheric surface in an axial direction.   
     
     
       26. An adhesion tester according to claim 15, wherein: the low friction contact points on the coupler are adapted to allow relative motion in an axial direction along the inclined peripheric surface of the dolly.   
     
     
       27. An adhesion tester, comprising: a frame defining a shaft extending along a longitudinal axis and a chamber for receiving a fluid under pressure;   a piston rod slideably engaged with a portion of the shaft and moveable along the longitudinal axis between a first position and a second position; and   a dolly pivotally mounted to the piston rod and having a surface adapted to be adhered to a coating of an underlying substrate when the piston rod is in the first position,   such that pressurized fluid introduced into the chamber exerts a force on the piston rod in a direction of the longitudinal axis, the force being translated through the dolly to the coating of the underlying substrate.